------------[ cut here ]------------
[CRTC:39:crtc-0] vblank wait timed out
WARNING: drivers/gpu/drm/drm_atomic_helper.c:1922 at drm_atomic_helper_wait_for_vblanks+0x763/0x8f0 drivers/gpu/drm/drm_atomic_helper.c:1921, CPU#0: syz.0.0/5312
Modules linked in:
CPU: 0 UID: 0 PID: 5312 Comm: syz.0.0 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
RIP: 0010:drm_atomic_helper_wait_for_vblanks+0x7a3/0x8f0 drivers/gpu/drm/drm_atomic_helper.c:1921
Code: 00 4d 8d 6e 20 45 8b 3f 4c 89 e8 48 c1 e8 03 80 3c 18 00 74 0e 48 89 fb 4c 89 ef e8 27 69 a3 fc 48 89 df 49 8b 55 00 44 89 fe <67> 48 0f b9 3a 49 bd 00 00 00 00 00 fc ff df 48 8b 5c 24 50 e9 cc
RSP: 0018:ffffc9000ecbf540 EFLAGS: 00010246
RAX: 1ffff11003ed800c RBX: dffffc0000000000 RCX: ffff88803c180000
RDX: ffff88801f18ca20 RSI: 0000000000000027 RDI: ffffffff90638e70
RBP: ffffc9000ecbf680 R08: ffffffff90576b37 R09: 1ffffffff20aed66
R10: dffffc0000000000 R11: fffffbfff20aed67 R12: ffff88801fa8a708
R13: ffff88801f6c0060 R14: ffff88801f6c0040 R15: 0000000000000027
FS:  00007f5f9cbe76c0(0000) GS:ffff88808c549000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5f9cba2fe8 CR3: 0000000013379000 CR4: 0000000000352ef0
Call Trace:
 <TASK>
 drm_atomic_helper_commit_tail+0x2e9/0x510 drivers/gpu/drm/drm_atomic_helper.c:1997
 commit_tail+0x2b1/0x3c0 drivers/gpu/drm/drm_atomic_helper.c:2074
 drm_atomic_helper_commit+0xa77/0xb10 drivers/gpu/drm/drm_atomic_helper.c:2312
 drm_atomic_commit+0x24e/0x2b0 drivers/gpu/drm/drm_atomic.c:1789
 drm_atomic_helper_set_config+0xe2/0x160 drivers/gpu/drm/drm_atomic_helper.c:3523
 drm_mode_setcrtc+0xa70/0x1d20 drivers/gpu/drm/drm_crtc.c:885
 drm_ioctl_kernel+0x2df/0x3b0 drivers/gpu/drm/drm_ioctl.c:817
 drm_ioctl+0x70e/0xba0 drivers/gpu/drm/drm_ioctl.c:914
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:583
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f5f9bd9e0d9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f5f9cbe6fe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f5f9c026090 RCX: 00007f5f9bd9e0d9
RDX: 0000200000000400 RSI: 00000000c06864a2 RDI: 0000000000000003
RBP: 00007f5f9be35024 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5f9c026128 R14: 00007f5f9c026090 R15: 00007ffd546fe7d8
 </TASK>
----------------
Code disassembly (best guess), 1 bytes skipped:
   0:	4d 8d 6e 20          	lea    0x20(%r14),%r13
   4:	45 8b 3f             	mov    (%r15),%r15d
   7:	4c 89 e8             	mov    %r13,%rax
   a:	48 c1 e8 03          	shr    $0x3,%rax
   e:	80 3c 18 00          	cmpb   $0x0,(%rax,%rbx,1)
  12:	74 0e                	je     0x22
  14:	48 89 fb             	mov    %rdi,%rbx
  17:	4c 89 ef             	mov    %r13,%rdi
  1a:	e8 27 69 a3 fc       	call   0xfca36946
  1f:	48 89 df             	mov    %rbx,%rdi
  22:	49 8b 55 00          	mov    0x0(%r13),%rdx
  26:	44 89 fe             	mov    %r15d,%esi
* 29:	67 48 0f b9 3a       	ud1    (%edx),%rdi <-- trapping instruction
  2e:	49 bd 00 00 00 00 00 	movabs $0xdffffc0000000000,%r13
  35:	fc ff df
  38:	48 8b 5c 24 50       	mov    0x50(%rsp),%rbx
  3d:	e9                   	.byte 0xe9
  3e:	cc                   	int3